Centuri Space Shuttle KC-6 (2 glider) build

Our Club had a Retro build session about a week ago, Most of the guys and gal were building SEMROC Clone kits. another member and I decided to do Centuri Space Shuttles.
I got lazy, and didn't Order the cones from Semroc but remembered HEY I have one of those in my collector kits stash
I looked it up on my master list and sure enough I didn't have one. I have 2. KEWL!!!! I'm gonna build one of them.
After scrounging around in the places I haved these things hanging I emerged covered in dust but with Centuri Kit KC-6 (5066) in hand according to the list a 1973 vintage kit. RED Plastic Nosecones????
So I scanned everything, including the very clean but a little yellowed decal sheet and began building the night before the meeting.
I'll Add more as I get the pics labled, but heres the begining of a very interesting build.

NOTE! if the little shuttle glides at all I'll be very surprised! Man is it NOSE heavy

Edit: Check out how Brown those tubes are

A look at the orbiter & power pod mounting dowel Scallops and lugs

Pod and orbiter seat from above

Actual construction starts at the Meeting the following night

One of the slightly interesting parts to this model, Centuri looked at the motor pylon as a potential weak point so has the builder laminate a couple pieces of the instruction paper to both sides.
it's an excellent way to make a part, wing or tail incredibly strong without adding much weight at all

Booster (mothership) which is actually the parasite glider on this model, canard installation... Oooops those are the wings for the orbiter DOH!

Before beginning this build, I weighed and measured all the kit parts thinking the Hollow molded plastic 2 piece plastic Nosecones would be lighter then solid balsa wood cones. Man was I Wrong!!!
These puppies are very heavy. I'll post the weights as an edit a little later..Left the note in the basement. Point being is these things are way heavier then the Balsa cones Jim Filler got from Semroc. Which i'm thinking can only help the little stubby wing Orbiter. More on that later

Before beginning this build, I weighed and measured all the kit parts thinking the Hollow molded plastic 2 piece plastic Nosecones would be lighter then solid balsa wood cones. Man was I Wrong!!!
These puppies are very heavy. I'll post the weights as an edit a little later..Left the note in the basement. Point being is these things are way heavier then the Balsa cones Jim Filler got from Semroc. Which i'm thinking can only help the little stubby wing Orbiter. More on that later

after removing the Orbiter wings from the boosters canard location I sanded off the little bit of glue build up and attached the correct parts. Luckly I didn't damage the wings druing removal so they should be fine when installed on the orbiter.

Before I go to much further rounding off the ends of the scalloped dowels should aid alignment and attachment of the push on Pod and slip over and on Orbiter.

Also check out the quality of the tube and seams on this 34 year old tube. Man all 4 various size pieces have and excellent suface to work with

next step to assemble the orbiter 2 piece tail. Here again you really have to pay attention to the parts layout as there are actually 2 pair of pieces that are very close.

While the tail is drying I assembled the remainder of the parts and offset centering rings on the Power Pod.

A tip is to insert the motor block with a spent motor casing marked to leave at least 1/8" of motor outside the motor tube, before installing the motor hook.
The instructions ask to have the motor hook placed Flush with the aft end of the motor tube which would make spend casing removal a real Pain without some sort of nozzle hook tool.
I opted to push the motor hook out 3/16" with the motor block just on the outside of the hook and allowed the motor pod to extend about 3/8" beyond the aft end of the orbiter.
We'll have to see of these modifications throw the boost balance off any more then adding a ton of tail weigth to the orbiter to try to get it to glide

another look at the power pod from the aft end showing the motor retainer hook extension.

Wow. Lots going on in the build of one of these. Thanks for the thread, John.

I agree on the quality of those old tubes. I'm slowly working away on a Centuri Buck Rogers Starfighter, and the tubes are beautiful. Alas, the diecut cardstock pieces are not.

I've got the Blast From The Past version of the Shuttle, but my construction photos are nowhere near as detailed as yours. You should write this up as an EMRR review. It would make for good reading, especially since it's a vintage kit.

Yes, very nice build thread. I'd love to see this on EEMR as well.

Thanks guys:
This has been a fun build. Maybe when I retire or stop flying I'll have more time to write about it. EMRR's been after me for awhile to write up stuff on my micros as well, I just havent' found or made the time to write up, edit, correct, rewrite, proof, etc....LABOR!!!! guess that's why I haven't added to the 17 or so Tech-Tips series either. So many Models Soooo little time.

I really like this pictorial thread formate, it's pretty quick, and far less Grammar sensitive.
Back to the build:
Here we slide the power pod on the booster to check the slot fit and match up with the dowel pins. I like the engineering on this set-up and LL reinforcements, quite ingenious I think, one of the Plus marks for most "Centuri" kits

One of the steps I forgot to photograph was using the orbiter bodywrap template to mark the Tail, wing, elevator and powerpod slot opening, Sorry my bad.
This step is important as it sets the cutout slot in the orbiters belly to allow the pod to advance to the Nose cone shoulder.
It also give mounting position and lines for the Vertical tail. at this point I attached the Tail. and made a second set of Cardboard wing and elevator support jigs similar to those used on the booster. I've found these things make wing/elevator or wing/canard alignment much easier.
After cutting out the pod slot and allowing the tail/orbiter to dry I had to do a "first fit up" of all three parts.
I don't recall if I mentioned this entire build is being done with Tite-bond II and Elmer's yellow carpenters glue including all fillets.
Heres the first fit-up

After this first fit up it occured to me, the ejection charge will be blasting unobstructed directly into the mostly open bottom of the two piece plastic nose cone. I don't like that idea at all, so I'm going to alter construction here just a little one more time by added a BT-60 size heavy centering ring center ( I never throw anything away) with a laminate of two layers of .004" thick Stainless steel tape to the Plastic shoulder base with ambroid cement attaching and covering the edges and tape.
I didn't stop at the time to take a photo of this process but here's a pic of the 2" wide stainless steel adhesive backed tape. (McMaster-Carr #76055A695). The stainless foil is .002" thick with .002" acrylic adhesive and is rated for up to 350°f makes pretty good bulkhead sheilds
An option could be a piece of aluminum soda tho Aluminum wouldn't hold up for as many flights.

next we need to add 15° up elevator to both Orbiter horizontal stabalizers. These are some fairly small parts so just for fun I make up a 3rd cardboard setting jig. all these "attachment and alignment jigs" are made from the back of a standard 8-1/2" x 11" paper pad..(See I told you I don't throw anything away LOL).
I'm also building on a 12" square piece of plate glass, to ensure the surface i'm building on is as flat as I can get

To aid in getting the wing and elevators level and aligned with the belly slot and tail I taped the body to the glass base while using a machanics square to check the vertical plum. once satisfied with the arangement the jigs are used to support but elevator stabs and wings while the tite-bond dired and Elmer's yellow glue fillets are applied.

After the Orbiter wood parts filles and forward attachment lug were attached it was time for the nosecones to be glued on by adding the adhesive backed paper strips to the shoulders ( yep the 1973 adhesive was still tacky) with the aid of a little elmer's yellow glue on the booster and ambroid cement on the orbiter.
I went with the Hot fuel proof Ambroid on the orbiter to help insulate the plastic from the ejection heat and shock as this Model Airplane cement retains a bit more flexibility than dryed carpenters glues. Epoxy wouldn't have resulted in any better bond with the cardboard tube so we went with something that doesn't become as brittle over time.
after drying our second fit up showed an unexpected result.
The powerpod when fully inserted in the Orbiter did not let the orbiter set completely on the 1/2" Scalloped forward retaining dowel. This was corrected by trimming about 3/16" off the forward end of the power pod. Now the Orbiter sets fully on the dowel. Man! what an amazingly firm connection between the three pieces but easily slip forward and backward, Again I bow at the Centrui's engineers efforts, Whoever engineered this attachment method really earned his keep

All the older plan I've seen on jimz and others have a pair of 65lb ligth cardstock canopies. These need to be cutout, folded up and glued. This kit must be from a later run as it came with vacuum formed .010" white styrene canopies. while very fragile out of the pack, they are pretty solid after attachment with liquid plastic cement. This is done by applying several passes with a brush soaked in Methylene Chloride (MC) or Testors liquid cement. If using Testors many passes may be needed to soften the styrene enough to "solvent weld" the two part into a single unit.
Once applied and allowed to dry, a little sanding around the edges removes any weld build up.
Last parts are the 4 piece booster wing elevator tabs and small reinforcing winglet triangles applied to the bottom of the wings. I used the original tabs but the Adhesive has dried up so elmer's carperters cement was used to attach and combine two tabs on each wing into a bendable up elevator. Last to be added are the small triangular bottom mounted winglet reinforcements. these don't show in the photo.
I noticed the Launch lug used to attach the orbiter to the booster rested well over the canopy on the booster. I trimmed this forward part off on about a 20° slope just for looks.

That's it... they are complete as far as construction goes.
Now's the time for some basic glide trimming, something I'm trouble at! and maybe a test flight before starting the finishing process.

Now lets talk a bit about those very heavy plastic nose cones.
the booster cone tipped the scale at 7.4g and the shoulder at 4.7g = 12.1grams for the unit. Not to bad considering the size of the glider. BUT!!!!! the orbiters smaller cone weighed in at 6.35g with the shoulder at 3.85g = 10.2g total.
Given the very stubby wings and small size of the elevators the orbiter is NOSE HEAVY to the unth! a couple tosses in the living room show it going almost straight down.
15°s of up elevator just don't do much at all. I'm going to add a bunch of clay to both side of the tail to see if I can get some sort of glide out of this orbiter, but well have to wait until Satrudays Sport launch to actually "field test" both gliders on grass before launch.
Maybe I can get Kevin, Scott, Robert Edmonds or one of the Good Glider trimming Experts to give me some guidence on this little bugger?
I'll try to get a few pic of the test glides and naked flight
Here's a 4 pic of the construction completed Space Shuttle KC6

View attachment 468b15e-sm_const. completed 4 view_06-10-07.jpg

John your skills are amazing! I read many of your posts here on TRF but comment little. Had to complement you on your work.

Thanks for sharing as you do.

John,

The Blast from the past clone recomended using 30 deg on the orbiter elevators. I did this and it results in a very shuttle like plumet er I mean glide, but it does glide. Sorry I should have chimed before. How much does your added bulked add to the orbiter?

The BFTP clone uses vacuformed nose cones that are very light, I also seem to remember someone using the Semroc cones hollowed out. Are the stock cones injection molded?

Great build thread! How are you going to paint it?

I've been wanting to do this build for a while now. John has done a great job documenting the original, peaking my interest even more. I'm real curious to see how the Semroc balsa cone versions do comparatively, so I can determine whether or not it's even worth trying. The BFTP clones seem to work the best, judging from the other threads I have seen in the past.

Originally posted by mach7
John,

The Blast from the past clone recomended using 30 deg on the orbiter elevators. I did this and it results in a very shuttle like plumet er I mean glide, but it does glide. Sorry I should have chimed before. How much does your added bulked add to the orbiter?

The BFTP clone uses vacuformed nose cones that are very light, I also seem to remember someone using the Semroc cones hollowed out. Are the stock cones injection molded?

Great build thread! How are you going to paint it?

Click to expand...

I've been building a Centuri Space Shuttle about once or twice a year now for many years. I have used Mike Jerauld BFTPR vacuformed cones for the shuttle and they make a big performance improvement. Unforunately, I haven't seen him offer them for sale in ages.

He was working on an upscale from Bt60 sized booster to bt80 sized which I was really looking forward too. Just for kicks and because I has a suitable balsa nose, I built a upscale shuttle at that size. It flew pretty good.

Wow John im jealous....of your vast kit collection and your skills Great work on the shuttle!

Originally posted by Micromeister

Given the very stubby wings and small size of the elevators the orbiter is NOSE HEAVY to the unth! a couple tosses in the living room show it going almost straight down.
15°s of up elevator just don't do much at all. I'm going to add a bunch of clay to both side of the tail to see if I can get some sort of glide out of this orbiter, but well have to wait until Satrudays Sport launch to actually "field test" both gliders on grass before launch.
Maybe I can get Kevin, Scott, Robert Edmonds or one of the Good Glider trimming Experts to give me some guidence on this little bugger?
I'll try to get a few pic of the test glides and naked flight
Here's a 4 pic of the construction completed Space Shuttle KC6

Click to expand...

I'm no Kevin, Scott or Rob but it should be nose heavy. When you think of it, the elevator is set to the 'pull up' position, so it's trying to push the tail down. To make it level out into a nice gliding attitude, the nose would have to be heavy. If the nose was light, the forces wouldn't balance and the shuttle would try and loop.

I used a vacuform nosecose which is very light. With that, I found was was surprised how well it glided. The booster will glide better than the shuttle. Most of my good flights though, the shuttle landed only a few seconds before the booster.

On launching, you should see the model roll and even corkscrew on the way up. To some extent this is a good thing. But if it is really really severe it will lead to a squirelly fight. I've always thought this is due to uneven booster elevon deflection. You can't really control that. Because it is made from paper, the elevons will deflect in the breeze. They can't be perfect, so one will deflect more than another. When the speed of the model slows down, they will pop back up again and allow for the booster to be trimmed for glide nicely.

Here's an interesting experience I had flying the model a few years ago. After a normal boost, the ejection charge blew my shuttle's vacuform nosecone off. That weighs almost nothing, so what happened is that the model stayed together instead of separating. The model, booster, shuttle and pod together in launch configuration began to glide. It was a poor glide, but it was clearly a glide.

To me, the model should have begun a balistic dive. After all, it was still balanced like it was a rocket. So it should dive to earth like a rocket. Because it didn't I concluded that when it was boosting, it really wasn't trimed to fly like a rocket either. The model is marginally stable and that's why some folks might experience arcing and generally poor stability on boost.

I flew it again with a bit of clay on the end of the engine pod, but I couldn't get enough up there to really make a difference. While cranking out a yet another example of this model, the thought struck me that it would be easy to set the dowels and launch lugs that are used to join the pod, booster and shuttle ahead of where the instructions call out. If the shuttle and pod were located an inch forward of where the plans call out, that it, flush with the boosters body tube, then you'd be significantly moving the boost CG forward while not affecting any glide CG positions. Since this model is about as much as a C6-3 can lift, adding weight, even only to the pod, is a bad idea.

I haven't tested this idea out yet, but it's where I'm going next time I build one.

Shawn